Windows has a sometimes misunderstood 260-character file path limit. The limit doesn’t prevent files from being placed on long file paths, it just keeps most Windows software from being able to index or search those files. They are there, you just can’t find them. They are like documents locked in a box you don’t know you have.
Once you know the files are there and what their location is you can browse to the folder location and open the file. This makes long folder paths one way that people can try to avoid having their files indexed or collected.
BeyondRecognition has had several occasions where an additional 2% of files on a drive had paths exceeding 260 characters and were missed by normal Windows text search and/or file collection software.
How Long File Paths Occur
Long file paths occur in several situations:
- Copying folders that contain embedded folders. When folders are dragged to other folders at different levels sometimes the resulting folder path exceeds the 260 characters.
- Unzipping Files. Zipped files can contain folder paths that, depending on the length of the path into which the zipped files are placed, may result in going over the 260 characters.
- Long File Names. File names are included in the 260-character limit, and using long file names can cause the total path to be over the limit.
- Mapping Drives. Mapping drives can result in combined file paths that are excessively long.
Measuring the Unknowns
Here’s one way to see if you have a problem with long file paths: Have your indexing or collection software create an audit log of all files on a drive, including the size of each file. Total the file sizes and compare that to the “space used” metric provided in Windows. You can obtain the space used number by right-clicking on the drive designator in Windows and selecting Properties. The difference can be files that are hidden because the overall path is greater than 260 characters.
Note that this problem can occur on Windows-based Cloud storage. If you use cloud storage you may be able to obtain the “space used” number by examining your bills from the cloud provider. Compare that number with the total file space as indicated by your collection software.
If you can’t account for all space used, you have a problem that may be caused by files being “lost” on long drives.
The best solution is to use indexing and collection software that is not subject to the 260-character folder path limitation of most Windows software.
BeyondRecognition’s Collector is a USB-based device used for logging and collecting files. It has a 2600 character limit on the total folder path, ten times the normal Windows limit. It also features onboard deNISTing, deDuping, compression, and encryption.